Project Summary (public abstract) Health care providers, insurance companies, and even politicians are encouraging individuals and populations to improve their fitness and health through self-monitoring. The hope is that awareness of one's activity, weight, sleep habits, etc. might motivate a person to be more active, eat better, and sleep more. In short, awareness might lead to a healthier and happier population. Smart activity monitors, some of which are small enough to replace the zipper on a jacket, be worn on the wrist, or clipped to a shoelace, can provide a variety of feedback to the wearer. The devices can display and share a variety of metrics including: steps taken, stairs climbed, distance travelled, activity duration, and battery status. Some have replaceable batteries that can last four to five months; others have batteries that never need replacing but must be recharged every five days or so like a cell phone. The capacity to wirelessly sync to a computer or smart phone enables personalized feedback and peer group sharing. Feedback can include: weekly summary statics by email; daily, weekly, monthly charts with population norms; achievement awards; and participation in contests. Peer group sharing is a particularly interesting feature as it enables the awareness of the activity levels of other invited individuals within a social network. Knowledge of peer group performance through social networks can be a strong motivator. While the health and happiness of many Veteran lower limb amputees might improve from the provision of these devices, it is unknown how many would embrace the technology and make it part of their everyday life. The major cohort of the proposed research is the aging Veteran who lost a lower limb due to either peripheral vascular disease and diabetes or combat-injuries sustained in Vietnam. These Veterans are among the 623,000 Americans who live with lower limb amputation; a population expected to grow to over 1.4 million by the year 2050. Importantly, many older, less-active amputees seek comfort, gain confidence, and maintain social standing by prioritizing relationships through direct, face-to-face contact. This finding suggests many in our cohort may not relate to an abstract level of function (step counts) and that internet-enabled social networks may be of little interest. However, there is recent evidence to suggest this older cohort are becoming more connected through the internet and now might be the time to challenge this stereotype. The goal of the proposed research is to determine if it is worthwhile to provide Veteran lower limb amputees with smart activity monitors. Our two specific aims are to: (1) Determine if Veteran lower limb amputees are willing to use smart activity monitors as part of their daily life, and (2) Discover if feedback of actual and goal activity levels with or without te use of an internet-based social network (peer group community forum) can elevate activity levels and maintain it over a prolonged period of time. We propose to provide smart activity monitors to a sample population of Veteran, below-knee amputees age 50 or older (n=90), teach them how to upload activity data with or without social network access to a peer group, and observe their participation and activity levels. The results will answer our question if Vetera lower limb amputees are willing to habitually wear smart activity monitors and if feedback from the devices, with and without the influence of an internet-based social network of the participants' peers, can have an influence over duration of the two year study. The proposed research will provide a thorough understanding whether or not an inexpensive device (<$60) can improve the mobility (and health) of Veteran lower limb amputees. If successful, our long-term goal is to pursue a nation-wide implementation of this technology.